title: Two-dimensional concurrent HMQC-COSY as an approach for small molecule chemical shift assignment and compound identification.
abstract: Chemical shift assignment is the first step toward the structure elucidation of natural products and other chemical compounds. We propose here the use of 2D concurrent HMQC-COSY as an experiment for rapid chemical shift assignment of small molecules. This experiment provides well-dispersed (1)H-(13)C peak patterns that are distinctive for different functional groups plus (1)H-(1)H COSY connectivities that serve to identify adjacent groups. The COSY diagonal peaks, which are phased to be absorptive, resemble (1)H-(13)C HMQC cross peaks. We demonstrate the applicability of this experiment for rapidly and unambiguously establishing correlations between different functional groups through the analysis of the spectrum of a metabolite (jasmonic acid) dissolved in CDCl(3). In addition, we show that the experiment can be used to assign spectra of compounds in a mixture of metabolites in D(2)O.
authors.affiliation: National Magnetic Resonance Facility at Madison, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Kaifeng
authors.initials: K
authors.lastname: Hu
authors.forename: William M
authors.initials: WM
authors.lastname: Westler
authors.forename: John L
authors.initials: JL
authors.lastname: Markley
mesh_terms: D002247:Carbon Isotopes; D003517:Cyclopentanes; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008722:Methods; D009930:Organic Chemicals / Q000737:chemistry*; D054883:Oxylipins; D011522:Protons; D012997:Solvents
chemical_list: D002247:Carbon Isotopes; D003517:Cyclopentanes; D009930:Organic Chemicals; D054883:Oxylipins; D011522:Protons; D012997:Solvents; C011006:jasmonic acid